Terror threat perception and its consequences in contemporary Britain

The terrorist attacks of 9/11, and subsequent terrorist acts around the world, have alerted social psychologists to the need to examine the antecedents and consequences of terrorist threat perception. In these two studies we examined the predictive power of demographic factors (age, sex, location), individual values and normative influences on threat perception and the consequences of this perception for behavioural change and close relationships. In study 1 (N = 100) gender, benevolence values and normative influences were all correlates of threat perception, whilst sense of personal threat was correlated with increased contact with friends and family. In study 2 (N = 240) age, sex, location, and the values of Openness to Change and Hedonism, all predicted threat perception, which in turn predicted behavioural change and relationship contact. Such findings point to the important role social psychologists should play in understanding responses to these new terrorist threats

On The Panel Unit Root Tests Using Nonlinear Instrumental Variables

This paper re-examines the panel unit root tests proposed by Chang (2002). She establishes asymptotic independence of the t-statistics when integrable functions of lagged dependent variable are used as instruments even if the original series are cross sectionally dependent. She claims that her non-linear instrumental variable (NIV) panel unit root test is valid under general error cross correlations for any N (the cross section dimension) as T (the time dimension of the panel) tends to infinity. These results are largely due to her particular choice of the error correlation matrix which results in weak cross section dependence. Also, the asymptotic independence property of the t- statistics disappears when Chang's modified instruments are used. Using a common factor model with a sizeable degree of cross section correlations, we show that Chang's NIV panel unit root test suffers from gross size distortions, even when N is small relative to T

Algebraic Rainich conditions for the tensor V

Algebraic conditions on the Ricci tensor in the Rainich-Misner-Wheeler unified field theory are known as the Rainich conditions. Penrose and more recently Bergqvist and Lankinen made an analogy from the Ricci tensor to the Bel-Robinson tensor $B_{\alpha\beta\mu\nu}$, a certain fourth rank tensor quadratic in the Weyl curvature, which also satisfies algebraic Rainich-like conditions. However, we found that not only does the tensor $B_{\alpha\beta\mu\nu}$ fulfill these conditions, but so also does our recently proposed tensor $V_{\alpha\beta\mu\nu}$, which has many of the desirable properties of $B_{\alpha\beta\mu\nu}$. For the quasilocal small sphere limit restriction, we found that there are only two fourth rank tensors $B_{\alpha\beta\mu\nu}$ and $V_{\alpha\beta\mu\nu}$ which form a basis for good energy expressions. Both of them have the completely trace free and causal properties, these two form necessary and sufficient conditions. Surprisingly either completely traceless or causal is enough to fulfill the algebraic Rainich conditions. Furthermore, relaxing the quasilocal restriction and considering the general fourth rank tensor, we found two remarkable results: (i) without any symmetry requirement, the algebraic Rainich conditions only require totally trace free; (ii) with a symmetry requirement, we recovered the same result as in the quasilocal small sphere limit.Comment: 17 page

Gravitational energy in a small region for the modified Einstein and Landau-Lifshitz pseudotensors

The purpose of the classical Einstein and Landau-Lifshitz pseudotensors is for determining the gravitational energy. Neither of them can guarantee a positive energy in holonomic frames. In the small sphere approximation, it has been required that the quasilocal expression for the gravitational energy-momentum density should be proportional to the Bel-Robinson tensor $B_{\alpha\beta\mu\nu}$. However, we propose a new tensor $V_{\alpha\beta\mu\nu}$ which is the sum of certain tensors $S_{\alpha\beta\mu\nu}$ and $K_{\alpha\beta\mu\nu}$, it has certain properties so that it gives the same gravitational "energy-momentum" content as $B_{\alpha\beta\mu\nu}$ does. Moreover, we show that a modified Einstein pseudotensor turns out to be one of the Chen-Nester quasilocal expressions, while the modified Landau-Lifshitz pseudotensor becomes the Papapetrou pseudotensor; these two modified pseudotensors have positive gravitational energy in a small region.Comment:

Characteristics of inhomogeneous jets in confined swirling air flows

An experimental program to study the characteristics of inhomogeneous jets in confined swirling flows to obtain detailed and accurate data for the evaluation and improvement of turbulent transport modeling for combustor flows is discussed. The work was also motivated by the need to investigate and quantify the influence of confinement and swirl on the characteristics of inhomogeneous jets. The flow facility was constructed in a simple way which allows easy interchange of different swirlers and the freedom to vary the jet Reynolds number. The velocity measurements were taken with a one color, one component DISA Model 55L laser-Doppler anemometer employing the forward scatter mode. Standard statistical methods are used to evaluate the various moments of the signals to give the flow characteristics. The present work was directed at the understanding of the velocity field. Therefore, only velocity and turbulence data of the axial and circumferential components are reported for inhomogeneous jets in confined swirling air flows

Amorphous metallic films in silicon metallization systems

The general objective was to determine the potential of amorphous metallic thin films as a means of improving the stability of metallic contacts to a silicon substrate. The specific objective pursued was to determine the role of nitrogen in the formation and the resulting properties of amorphous thin-film diffusion barriers. Amorphous metallic films are attractive as diffusion barriers because of the low atomic diffusivity in these materials. Previous investigations revealed that in meeting this condition alone, good diffusion barriers are not necessarily obtained, because amorphous films can react with an adjacent medium (e.g., Si, Al) before they recrystallize. In the case of a silicon single-crystalline substrate, correlation exists between the temperature at which an amorphous metallic binary thin film reacts and the temperatures at which the films made of the same two metallic elements react individually. Amorphous binary films made of Zr and W were investigated. Both react with Si individually only at elevated temperatures. It was confirmed that such films react with Si only above 700 C when annealed in vacuum for 30 min. Amorphous W-N films were also investigated. They are more stable as barriers between Al and Si than polycrystalline W. Nitrogen effectively prevents the W-Al reaction that sets in at 500 C with polycrystalline W